The present invention is generally directed to toner and developer compositions, and more specifically, the present invention is directed to positively, or negatively charged toner compositions, or toner particles containing certain additives of silicas especially coated fumed silica surface additives, and wherein the additives selected are for example, of a large size diameter of from about 20 nanometers to about 100 nanometers, preferably from about 30 to about 50 nanometers and more preferably in embodiments about 40 nanometers in diameter. With the toners of the present invention, in embodiments thereof a number of advantages are achievable, such as excellent triboelectric charging characteristics, substantial insensitivity to relative humidity, especially humidities of from about 20 to about 80 percent, superior toner flow through, high stable triboelectric charging values, such as from about 15 to about 35 and more specifically from about 16 to about 24 microcolumbs per gram as determined for example, by the known tribo blow-off technique using a Faraday cage and wherein the toners enable the generation of developed images with superior resolution, and excellent color intensity. Important advantages associated with the toners of the present invention is the enablement of high transfer image efficiencies of, for example, greater than about 90 percent, and more specifically from about 90 percent to about 97 percent, and yet more specifically from about 90 to about 95 percent, and excellent image developability wherein images with high resolution, substantially no defects, such as scratches, non-uniform image density, and excellent optical densities determined by a Macbeth 1200 series optical densitometer, such as from about 1.2 to about 1.4 or greater are obtainable.
The aforementioned toner compositions can contain colorants, such as pigment particles comprised of, for example, carbon black, magnetite's, or mixtures thereof, cyan, magenta, yellow, blue, green, red, brown, or white components, or mixtures thereof, thereby providing for the development and generation of black and/or colored images, and in embodiments single component development wherein a carrier or carrier particles are avoided. Thus, the toner and developer compositions of the present invention can be selected for electrophotographic, especially xerographic, imaging and printing processes, including color and digital processes.